Enable a bunch of types2-related error tests to run successfully, so
they no longer have to be disabled in run.go.
- directive.go: split it into directive.go and directive2.go, since the
possible errors are now split across the parser and noder2, so they
can't all be reported in one file.
- linkname2.go: similarly, split it into linkname2.go and linkname3.go
for the same reason.
- issue16428.go, issue17645.go, issue47201.dir/bo.go: handle slightly
different wording by types2
- issue5609.go: handle slight different error (array length must be
integer vs. array bound too large).
- float_lit3.go: handle slightly different wording (overflows
float vs cannot convert to float)
I purposely didn't try to fix tests yet where there are extra or missing
errors on different lines, since that is not easy to make work for both
-G=3 and -G=0. In a later change, will flip to make the types2 version
match correctly, vs. the -G=0 version.
Change-Id: I6079ff258e3b90146335b9995764e3b1b56cda59
Reviewed-on: https://go-review.googlesource.com/c/go/+/368455
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This allows more precision and matches types2's behavior.
For backwards compatibility with gcimporter, for now we still need to
write out declared constants as limited-precision floating-point
values. To ensure consistent behavior of constant arithmetic whether
it spans package boundaries or not, we include the full-precision
rational representation in the compiler's extension section of the
export data.
Also, this CL simply uses the math/big.Rat.String text representation
as the encoding. This is inefficient, but because it's only in the
compiler's extension section, we can easily revisit this in the
future.
Declaring exported untyped float and complex constants isn't very
common anyway. Within the standard library, only package math declares
any at all, containing just 15. And those 15 are only imported a total
of 12 times elsewhere in the standard library.
Change-Id: I85ea23ab712e93fd3b68e52d60cbedce9be696a0
Reviewed-on: https://go-review.googlesource.com/c/go/+/286215
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
The float32 const conversion used to round to float64
and then use the hardware to round to float32.
Even though there was a range check before this
conversion, the double rounding introduced inaccuracy:
the round to float64 might round the value further away
from the float32 range, reaching a float64 value that
could not actually be rounded to float32. The hardware
appears to give us 0 in that case, but it is probably undefined.
Double rounding also meant that the wrong value might
be used for certain border cases.
Do the rounding the float32 ourselves, just as we already
did the rounding to float64. This makes the conversion
precise and also makes the conversion match the range check.
Finally, add some code to print very large (bigger than float64)
floating point constants in decimal floating point notation instead
of falling back to the precise but human-unreadable binary floating
point notation.
Fixes#8015.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews, r
https://golang.org/cl/100580044
